Sleeve valve internal-combustion engine



Nov. 19,v 1929. H. R. RllcARDo 1,735,975

SLEEVE VALVE INTERNAL COMBUSTION ENGINE Filed Aug. 6, 1928 2 Sheets-Sheet l f' am Nov. 19,- 1929. H. R. RICARDo 1,735,975

SLEEVE VALV INTERNAL COMBUSTION ENGINE Filed Aug.6, 1928 A l ZShetS-Sheet 2 Patented Nov. 19, 1929 HARRY RALPH RICARDO, or LoNDoN, ENGLAND SLEEVE VALVE INTERNAL-COMBDSTION ENGINE Applicationled August 6, 1928, Serial'lo. 291,787, and in'-Great .Britain August 26, 1927. I

This invention relates to four-cycle interl nal combustion engines of the' kind in which the inlet and exhaust ports are controlled by a single sleeve Valve having a combined oscillatin and reciprocating motion. In such engines the charge enters the cylinder more or less tangentially owing to the lateral motion of the sleeve while opening tlie inlet ports, and thus' causesthe charge to swirl or rotate about the cylinder axis. This charge swirlv has been found to have a rofound influence on the process of com ustion and the object of the present invention is to controlthis swirl so as to produce the best results.

Whilev ay certain amount of swirl-is advantageofus in that it reduces detonation, too much swirl gives trouble through centrifugal separation .of the liquid fuel in the charge and excessive heat loss which inhibits the rapid spread of the flame.

According tothe ,present invention thev passages of eachcylinder leading the charge to the inlet ports in the cylinder wall arel so formed as to reduce to a'suitablevalue this tendencyI of the charge to `rotate about the cylinder axis. Conveniently this may be ef fected by so disposing the -passages that the charge approaches the portswith a tangential flow in a direction opposite to that of the natural swirl. Alternatively guides or bailies may be provided in the passages or ports which induce the charge to enter the cylinder in a more orless radial direction.

In the case of multi-cylinder engines constructed according to this invention the inlet passages of each individual cylinder, or the inlet'ports of each cylinder are constructed and arranged as above described so that the 0 swirlin every cylinder is reduced to lthe required extent and therefore the performance ofthe engine as a Whole is improved;` y

The invention may be carried into practice in various ways but Vtwo alternative con- 5 structions according to this invention are illustrated by wayv of example in the accompanying drawings, in which Figure 1 isanelevation partly in section of an engine of the kind to which the present.

invention is applicable,

Figure.2 shows a section on the line 2-2,ofl Figure 1 of an engine having the inlet ports arranged 1n known manner, showinghow in prior constructions'excessive swirling of the chargeA about the combustion chamber axis is caused, y 'Figure 3 shows a similar view-to Figure 2 of one arrangement of inlet ports'acoording to the present invention, and

Figure 4 is a similar view to Figure-2 of anotherarrangement of ports according tothe present invention. v i

In the construction illustratedv in Figure 1, the enginecomprises a crankv case Acontaimng a crankshaft Aland having 'mounted 6" thereon a water-'cooled cylinder B, the cylin#A der B being closed at its upper end by apluglike cylinder head C. Disposed within the cylinder B is a sleeve valve D to which is im--z parted in known in anner a combined oscillati ingand reciprocating motionby a crank pin D1 on a lay shaft D2 driven from the crankshaft at half crankshaft speed by. suitable.. gearing. A piston E connected to the crank-v shaft Al by a connecting rod E1 reciprocates within the cylinder B.

In engines of this type the inlet ports open laterally. when the motion'of thel sleeve is mainly oscillating.- Thus in .the known arrangement of inlet ports shown in l'Figure 2 wherein a cylinder B1 is provided with three lnlet ports F communicating through acornmon passage F1 with .a central inlet opening F2, and controlled by .asleeve valve H'which also controls two exhaust ports G, the charge enters ythe cylinder through 'the ports F with a tangential component opposite to that of the sleevemotion 'during the opening period as indicated by arrows, -with A the result that an un'desirably rapid rotation of the charge'about the cylinder-axis tends to take place. When the inlet ports are fully opened there i's no tendency for the charge to enter tangentially through the central port F but there is a tendency for the charge to enter tangentially through thetwo side .ports F. The tangential components of the flow through these side ports, however, are" 'equal and l'opposite so that on the whole at this 'periodo the opening of the valve there is v10ov no tendency to'iset up a swirl. There is, however, little or no tendency also to check the swirl set up during the'initial' opening-- period ofthe inlet ports with the result that atthe end of the inlet period the char e tendaA to rotate about the cylinder axis wit -undesirable rapidity.

In the construction. accordingito'tllis invention illustrated in Figure 3 wherein the arrangement issuch as to tend tojcheck this excessive swirl, the engine comprises a cylin- 1 Figure 3, however, the

" opening der B2 containing a sleeve valve H1 control.

' to enter the cylinder during vthe later parts while during the initial o l axis of .the combustion chamber,

i v of the inlet period in such a direction-as v to counteract the swirl normally set up during the earlier part of the inlet openlng per1o'd.

Further, the 4inlet .ports Fs .are .conveniently formed with inclined edges or an overhanging. lip as indicated at'F6 so as to assist this .counteracting flow.

it will be seen' that ening of the inlet e set up about the Withfthis arrangement ports a swirl will tend to later portions of the inlet port opening,jthe

charge will pass Vthrough the inlet ports in a direction tending to counteract or check the i swirl initially set up whereby the speed of rotation of the charge about the Vcylinder l v F8 and opening axis at the end of the inlet period will tend to be reduced to a" desirable value.

to this invention shown in Figure 4, the cylinder'Bf is provided with three inletportsv F? communicating through a chamber-Fa. with a'n inlet opening F9 and two exhaustports G,all thesev ports as well as the passage F being arranged substanf u t tially asjm the construction 'Shown'n Figure 2. The

ports are controlled by .la sleeve v'lveHi- In the arrangement shown 1n Figure 4,

however, a` seriesof guide vanes J Yextend a across the inlet'ports F1, being substantially radial w1th. respect to ports todo so these guide vanes the cylinder axis so asto tend to cause the charge entering the .cylinder through thesei. substantially .radially whereby the tendencyforthe charge to rotate about the cylinder axis -is reduced. Alternatively,

the vanes may be set-obliquely so as to induce a `swirl which will tend to` counteract any I natural swirl which I nay'beset upwithin' thecylinder during the earlier portion ofthe f opening period of the inletports The/Yanes J'vma'y'be cast a greater part' of the charge tends during the.

integral the cylinder or may be made of sheet metaland subsequently placed in position.

It is to be understood that the construcample only and that tha' may be modified in various ways without eparting from thisinvention.

What I claim `my invention and desire to secure by Letters .Patent is':-'-

1. A four-cycle internal combustion engine including in combination 'a cylinder having inlet and exhaust openings in its wall, a-

sleeve valve disposed withinthe' cylinder and A having ports therein adapted to register with theinlet and outlet openings .respectively during the inlet and exhaust periods, means for imparting to the sleeve a combined oscil- `lating'and reciprocating motionsuch that the inlet ports 'commence to register with the.v 'i

inlet openings when the motion of the sleeve is mainly oscillatory,- and means forleading the charge through the inlet openings 'in such a'directio'n as toV counteractat least partially thef rotation of thecharge about the-cylinder axis whichtends vtobeprod-uced during the initial yopening period of the inletports.

2. A four-'cycle internal combustion engine including in combination a cylinder having inlet and exhaust opening vin its wall, af sleeve valve disposed'within the" yinder and havmg ports therein adaptedA o register with V'the lnlet and outletopenlngs inthe cylinderA respectively during the -inlet and exhaust periods, *means for imparting to the -sleeve a combmed osclllatin .and reciprocating mo tion lsuch that the inletrports commence'to register with the 'inlet openings when. the Ino-- tlon. of the sleeve :is mainlygoscillatoly, the formation of the .inlet openings being such as to tend to cause the charge to .pass there- In the alternatlve arrangement according` through 'at' least .duringthe -laterportions chargefabout the cylinder 'axis which' tends to produced -during V'the vinitial opening periodof the-inletport's. i

wall, a sleeve valvedispos'ed within the cylinthe'cylinder respectively during the inlet and exhaust perio l s, meansg for imparting t'o the sleeve a combined oscillating and reciprocat- 'of the inlet period in such a .direction as to counteract the rotational motion ofv the vfour-'cycle internal combustion en-v gine ln'cluding -in .combination a cylinder -havlng inlet Aand exhaust' openings in its "der and 'having' ports vtherein adapted to Y register wlth the inlet and .outlet openings in ing motion such 'that the inletports comlas in such a manner that the charge 'approaches the openings 'in a direction. having a. tangential .componentopposite to 'that which tends Vto be imparted tothe char'gewithin the cylin- 'loon' oillatory, and a passage leading the charge to at least the majority of the inlet openings in such a manner that the charge approaches the openings in a direction having a tangential component opposite to that which tends to be imparted to the charge within the cylinder during the initial opening period of the inlet ports, at least one edge of each inlet port which lies substantially parallel to the cylinder axis being inclined so as to assist the tangential entry of the charge in the desired direction.

In testimony whereof I have signed my name to this specification.

auf

HARRY RALPH RICARDO. 

